1. Field
One embodiment of the present invention relates to a telephone exchange apparatus configured to treat communication networks such as an Internet Protocol-Q-Signaling (IP-QSIG) network, a session initiation protocol (SIP) network and integrated services digital network (ISDN) which are different in communication protocol one another, and relates to a telephone system in which a plurality of telephone exchanges are connected, for example, via the IP-QSIG network one another.
2. Description of the Related Art
In recent years, an Internet Protocol (IP) telephone system which interactively transmits and receives images and audio as packet data in real time via an IP network has become widely used. The IP telephone system may perform extension communication and external line outgoing and incoming call among main apparatuses to be connected to the IP network as well as for each main apparatus though the IP network.
Meanwhile, the IP telephone system has become treat packet data of various communication protocols in the main apparatuses. In this case, each main apparatus is provided with an exclusive interface unit corresponding to various communication protocols and an exclusive communication controller for controlling the interface unit (e.g., Jpn. Pat. Appln. KOKAI Publication No. 2004-336144).
However, since each main apparatus needs an exclusive interface unit and an exclusive communication controller, adding a communication line with a new communication protocol requires additional setting of its exclusive interface unit and its exclusive communication controller, thus the configuration of each main apparatus becomes large in size and high in cost.